A rotationally invariant Lagrangian is

.

examples of scalars:

speed of light:

is a 4-vector is a lorentz scalar.

proof:

is a 1 form.

This implies that the inverse transformation: so .(covariant vectors)

contravariant vectors follow .

is a lorentz scalar.

source psfile jl@crush.caltech.edu index

relativistic_kinematics